A string of withdrawals ⁠from the Canadian Open underscored concerns ⁠that professional tennis’s lengthy calendar and expanded top-level ⁠events are increasing injury risks, the Professional Tennis Players Association has said.The players’ advocacy group said it was saddened but not surprised by the absences from the tournament, arguing that reduced recovery time between tournaments was contributing to injuries occurring earlier in the season and becoming more serious.In Montreal, the men’s event was hit by the withdrawals of ‌world No 1 Jannik Sinner and 24-times grand slam champion Novak Djokovic, while Carlos Alcaraz was also sidelined with a wrist injury. Hometown favourite Felix Auger-Aliassime also pulled out because of a back injury before his opening match.On the women’s side, defending champion Victoria Mboko, Wimbledon finalist Karolina Muchova, Emma Raducanu and Jasmine Paolini are also missing the tournament with injuries.Tournament organisers said last month that recurring late withdrawals from ⁠Masters 1000 events had become a wider issue for the sport.Clouds hang over the Stade IGA during a rain delay at the Canadian Open in Montreal. Photo: Getty ImagesThe PTPA said it had collected and analysed injury data ‌from more than 30,000 professional matches across all levels of the game over the past eight years in a project launched three years ago with its medical director, Dr Robby Sikka.